In case you just upgraded your iOS powered device to iO7 or any other version and now this device runs slower than it used to, this resetting of the device procedure might speed things up.
You don't need Photoshop or some other advanced piece of software to resize a large number of images at once. You can use Microsoft Office Picture Manager which is part of the Office suite.
You will learn how to manipulate a photograph in a way it will look like an object, melting snowman in my case, is sticking out of a photo using Photoshop CS5.